I ducked under tree branches, waded through tall grasses and scanned ahead to avoid the golf ball-size spiders that seemed to loom everywhere on Santa Cruz Island, part of Ecuador's Galapagos National Park. Beads of sweat rolled down my neck.

I had been hiking for an hour with four traveling companions and two guides on what was barely a path, and the humid heat had me wondering, "Why do I think this is fun? I could be sipping daiquiris at some swim-up pool bar right now like most people do on vacation."

But minutes later, rounding a bend, I forgot all the misery: About 30 feet ahead, amid trees and brush, stood a giant tortoise on the tips of its thick legs. Its long neck stretched so high that it easily cleared 4 feet tall. For a split second I thought it was a dinosaur.

Whoa! Who needs a swim-up bar when you can explore the Galapagos Islands on foot?

While 72 percent of international tourists see the volcanically formed islands by small cruise ship and take brief shore excursions, my group of five travelers, all avid backcountry campers, wanted to immerse ourselves in the islands' wilderness. The best way to do that, we concluded, was to stay on dry land. Our decision put us on the path of a burgeoning way to experience the Galapagos, not to mention on the path of that awe-inspiring tortoise.

Visitors aren't allowed to explore the 97 percent of the islands that make up the Galapagos National Park without a guide. We'd signed up for an REI Adventures land-based, multi-sport tour, which paired an REI guide with a national park guide to lead us hiking, mountain biking, snorkeling and kayaking. Each evening we returned to hotels in the islands' tiny towns, where we dined at local restaurants and wandered the streets and beaches on our own.

IF YOU GO

For more information on REI Adventure tours of the Galapagos, as well as other destinations, go to www.rei.com/adventures or call 1-800-622-2236.

I felt a little conflicted: We had traveled thousands of miles to see one of the most unusual and delicate natural areas on the planet, yet we slept in modern hotels with air conditioning and, in one case, an infinity pool overlooking the ocean. Staying there meant we would use precious fresh water, make trash and consume electricity. Were we harming the islands by staying on them?

Certainly all tourism has an impact. But our guides assured us that our tour at least had a beneficial side: We were keeping much of our money local.

The population of human residents in the Galapagos has exploded. The government restricted immigration to the islands in 1998, but residents continue to bring in spouses and have children. Today, there are more than 25,000 people living there, up from a couple thousand in the 1950s. Some locals had earned a living by harvesting natural resources such as fish and marine animals. Instead of spending our money eating and sleeping on a boat, we were giving the locals an alternate way to work.

"You're helping the people, helping the town," said 65-year-old Evelina Correa, who moved to the islands in the 1980s and runs a roadside restaurant. "The boat tours are great, but the big boats, they won't leave much money in the town," she said.

At the same time, our REI tour worked to turn us into true environmental stewards. Our hotels featured energy-efficient lights, timed showers and placards encouraging guests to turn off the air conditioning when leaving the room. Our REI guide, Felipe Meneses, spoke frequently about humans upsetting the ecosystem. He picked up every piece of trash he saw.

In a contained environment like the Galapagos, it seemed, every small act could make a difference. Park officials have been working to eradicate non-native plants and species such as goats, rats and feral cats, all introduced by humans.

Feeling the Earth's inner fury

Meneses knew the best way to make us care about the environment was to showcase it. Most mornings, our alarm clocks buzzed before sunrise. We rose early to beat the heat; our trip in March meant we saw the islands in the warm, rainy season. Vegetation was lush and green, and we didn't need wet suits for snorkeling. But it also turned out to be smack in the middle of a hot streak, with temperatures reaching into the 90s and high humidity.

After a hearty breakfast at our hotel, Meneses started each adventure with an enthusiastic, "Vamonos!" Let's go!

On the island of Isabela, we got a close-up look at how the young islands were formed with a 10-mile hike on the still-active Sierra Negra volcano, which last erupted in 2005. Reaching the rim, we couldn't help but gasp when we peered across a 5-mile-wide caldera containing a vast, even field of hardened black lava. We walked atop giant ribbons of multicolored lava that had cascaded down the mountain's side. Our national park guide squatted down in one spot and motioned for us to come over. One by one, he invited us to stick our hands inside a small hole in the sharp rocks. Hot! We were feeling the Earth's inner fury.

On the hike back, we stopped precisely at noon to take pictures of our shadows. It was the spring equinox, and we stood just a few dozen miles below the equator. The sun, directly overhead, cast shadows straight onto our feet.

The volcanoes were spectacular, but like most tourists to the Galapagos, we were eager to see wildlife. This is where Charles Darwin traveled 176 years ago and noticed subtle differences in species on each island, leading to his theory of evolution. Those variations still exist among the tortoises, lizards and birds on the archipelago's 13 main islands.

Seeing the creatures up close was not a problem. With relatively limited exposure to humans, Galapagos animals didn't automatically run at the sight of people.

Blue-footed boobies sat calmly on rocks as we kayaked nearby. Frigate birds puffed up their red balloon-like throats in a mating ritual. Small Galapagos penguins waddled on shoreline rocks.

On one short hike, we saw hundreds of marine iguanas piled atop each other. They blended in with the black lava beneath them.

"Watch out!" I gasped to my sister just ahead of me. "You almost stepped on that iguana's tail."

Down that same path, on a sandy beach, curious young sea lions wandered up to our group. One pup, which our guide estimated to be two weeks old, scooted toward us on his flippers, his big brown eyes seeming to plead for cuddling. "Awwww," we all cooed.

"That's the problem," our guide said. "These guys are so cute and they would let you pet them, but then it would be the end of them."

A pup that young could be abandoned by its mother if it smelled like humans, he explained. We had to move on. Vamonos.

Face to face with sea lions

As we snorkeled near the shores of San Cristobal Island, slightly older sea lion pups frolicked in the surf, zooming up face-to-face with our masks underwater. Even with a snorkel in my mouth, I couldn't help but laugh as they played keep-away with a stick. When one pup dropped the stick in front of me underwater, I grabbed it and waved it like a wand, tempting my new friends to snatch it away. Just as I let go, one did.

Later, in the deep waters off Kicker Rock, a monolith that juts 485 feet above the surface, sea turtles, rays and sharks greeted us as we floated in the choppy water.

When each day's adventure ended, we relaxed with a nice meal and a stroll through the safe streets of the small towns, getting a glimpse of how the locals live. Like a small town in Minnesota, residents knew one another, but didn't seem bothered by the strange tourists in their midst. They left doors and windows wide open to catch cool evening breezes. Children played in town squares, no parents in sight.

On the beach, we used the light of the moon to look for just-hatched sea turtles crawling toward the surf. Turning our heads upward, we could see both the Big Dipper and the Southern Cross.

Still, to me, nothing compared to the giant tortoises on the wilderness hike. The path, I learned later, wasn't made for humans: The tortoises themselves had forged it through the brush. No wonder it had been so tough to traverse.

Our group stood motionless, watching the first of several gentle giants on their path, its E.T.-like face slowly scanning its surroundings.

Scientists estimate some giant tortoises have been around more than 150 years. I couldn't help but wonder as I stared at it: What had this tortoise seen? How much did the islands change around it? Could it have come face to face with Darwin?

After a few minutes, the tortoise slowly withdrew its legs and neck, letting out a low, Darth Vader-like hiss.

I could have watched him for hours, but we had to move on. Our six days on the islands -- exploring the terrain step-by-step and paddle-by-paddle -- were coming to an end, and suddenly the trip felt too short.

Sure, holiday baking traditions are great. But isn't it time to try a new sweet treat this year? The Holiday Cookie Finder has every winning recipe from our annual baking contest from the past 14 years.

It's tempting to drop everything and roam Minnesota to catch all the crimsons and golds at this time of year. But who has time for that? We've found your leaf-peeping match. Just follow our flow chart.